The length of insurance-mandated medically supervised diet programs for precertification of bariatric surgery varies significantly. In the state of West Virginia policies range from 3 months to 12 months of insurance-mandated medically supervised diet. The current study examined the effects of prolonged insurance-mandated medically supervised diet on weight loss results three months after sleeve gastrectomy.


195 patients who underwent laparoscopic sleeve gastrectomy over a 12 month period within an accredited university based practice were used for the study. All patients underwent a medically supervised nutrition program and were categorized into three groups, those that had 3 months or less(N=38), 4 to 6 months(N=116), and greater than 6 months(N=41). The percentage of excess weight loss(%EWL) was compared across the three groups using Analysis of Variance(ANOVA).


The %EWL from initial consult to day-of-surgery increased with increasing insurance-mandated requirements (5.07 ±8.24%EWL for 3 months, 7.84 ±8.77%EWL for 4 to 6 months, 11.34 ±9.49%EWL for 6+ months F=5.04, p=0.01). Inversely, the %EWL three months after operation decreased with increasing insurance-mandated requirements (39.72 ±11.64%EWL for 3 months, 35.85 ±11.18%EWL for 4 to 6 months, 27.70 ±10.54%EWL for 6+ months; F=12.54, p=0.00).


Longer insurance-mandated medically supervised nutrition requirements led to increased preoperative weight loss. Even with accounting for increased preoperative weight loss, patients having longer medically supervised nutrition requirements achieved lower 3 month postoperative weight loss. Delaying bariatric surgery for additional preparation time beyond 3 months does not improve postoperative weight loss and in this study was detrimental.